New ro unit help

[fishkeeprian]

Hello I have just got a new RO unit as below and I'm getting a reading of 3ppm from my water out and not sure why I'm not getting 0 as I'm sure this unit is capable of.

I've ran the unit for a while (made about 25l of water)and flushed it but made no difference any ideas please?

https://www.vyair.com/pumped-4-stage-reverse-osmosis-50-gallons-per-day-water-filter-system-including-di-resin-stage.html

Thanks

 

[lpsouth1978]

Are you storing the water at all before testing, or are you taking it straight from the output and testing? What is the TDS of your feed water (from the tap), and after the membrane (before DI)? Also, What did you calibrate your TDS meter with?

 

[fishkeeprian]

Are you storing the water at all before testing, or are you taking it straight from the output and testing? What is the TDS of your feed water (from the tap), and after the membrane (before DI)? Also, What did you calibrate your TDS meter with?

Not storing the water before testing the 3ppm reading Straight out the output. The reading I'm getting is from the inline tds metre. The water going in 234ppm, not sure how to test before the Di?
I've not calibrated the tds metre it says it's ready to use out the box.

 

[lpsouth1978]

It is hard to say why you are getting 3ppm. Assuming 96% rejection from the Membrane, you should only be around 10ppm before DI. The DI resin should easily be able to get you down to 0ppm. My first thought would be that the TDS meter is not properly calibrated. If the meter can be calibrated, I would start there. You could also get an inexpensive hand held TDS meter, calibrate it with calibration solution (NOT RO water) and see if you get a different result. Maybe someone in your are has one and can double check the TDS for you.

 

[fishkeeprian]

Agreed. Think I will start with tds metre calibration. Which fluid do I need? Is it the 342ppm fluid to calibrate?

Also do I need to flush the unit in between each use?

 

[lpsouth1978]

Agreed. Think I will start with tds metre calibration. Which fluid do I need? Is it the 342ppm fluid to calibrate?

Also do I need to flush the unit in between each use?

Yes, I use 342ppm calibration solution for mine. Flushing the membrane before making water won't really improve the TDS of your RO water, but it will prolong the life of your membrane, and keep it from clogging and slowing.

 

[fishkeeprian]

Yes, I use 342ppm calibration solution for mine. Flushing the membrane before making water won't really improve the TDS of your RO water, but it will prolong the life of your membrane, and keep it from clogging and slowing.

How long of a flush before I produce water?

 

[lpsouth1978]

It doesn't need much. I just flush mine for a couple of minutes.

 

[Uncle99]

Your pushing water up the DI cartridge right?
Down can lead to channeling and a slight increase in TDS output.

Your TDS in coming is a bit high at 234, so not a big surprise, make sure there are no cracks or small leaks, if you get a hand held, check in the RODI tank, not a glass.

 

[fishkeeprian]

It doesn't need much. I just flush mine for a couple of minutes.

I got a non return valve as part of the connecting kit but doesn't say where this should be fitted. Any ideas?

 

[fishkeeprian]

Your pushing water up the DI cartridge right?
Down can lead to channeling and a slight increase in TDS output.

Your TDS in coming is a bit high at 234, so not a big surprise, make sure there are no cracks or small leaks, if you get a hand held, check in the RODI tank, not a glass.

What do you mean up?

 

[lpsouth1978]

What do you mean up?

He is talking about the DI canister. Try Positioning your DI canister vertically, so the water goes from the bottom to the top. This eliminates the channeling of water so you don't have and get through without coming in contact with the resin.

I don't know where is best to install the check valve, as I haven't ever used one on an RO system.

 

[fishkeeprian]

He is talking about the DI canister. Try Positioning your DI canister vertically, so the water goes from the bottom to the top. This eliminates the channeling of water so you don't have and get through without coming in contact with the resin.

I don't know where is best to install the check valve, as I haven't ever used one on an RO system.

The DI canister is already vertical.

 

[outssider]

What do you mean up?

the water should be going from the ro unit to the bottom of the resin chamber and going up and then out...

 

[fishkeeprian]

He is talking about the DI canister. Try Positioning your DI canister vertically, so the water goes from the bottom to the top. This eliminates the channeling of water so you don't have and get through without coming in contact with the resin.

I don't know where is best to install the check valve, as I haven't ever used one on an RO system.

The unit has a built in flush valve and it says installing it inline with the waste pipe.

Do I flush before and after producing water?

 

[Uncle99]

What do you mean up?

Water can flow either top to bottom and then to holding tank, or bottom to top.
I have seen both hookups, but when the water comes from RO and is pushed from the bottom of the DI cartridge, it ensures an even contact with the resin at all times.

 

[fishkeeprian]

How do I know if it is being push from bottom or top?

I also have a couple of ball valves so if I put one on the out to slow the water down coming out so it has more contact time with the Di will this help?

 

[Uncle99]

How do I know if it is being push from bottom or top?

I also have a couple of ball valves so if I put one on the out to slow the water down coming out so it has more contact time with the Di will this help?

I use my RODI unit without modifications, changing things (as I found out) sometimes leads to more TDS and proves I know little of water purification techniques.

There must be a water line coming out of your RO membrane canister right?
This line would take the RO water and deliver it to the DI canister. It is beneficial that this line enters the DI canister (which should be standing length wise vertically) at the bottom. At the top, you should have another line which goes to your RODI holding tank.

If the RO water enters the DI canister at the bottom, the water had no choice but to move upward through the resin, out the top, and into the holding bucket.

 

[homer1475]

If the RO water enters the DI canister at the bottom, the water had no choice but to move upward through the resin, out the top, and into the holding bucket.

You do realize that all canisters have the input/output lines at the top of the canister? It's the inner cartridge and whether the input line is at the top of the cartridge or on the side determines where the water goes?



If the incoming water is on the outside of the inner cartridge, it's being pushed up through the resin. If the incoming water is at the top of the cartridge, the the water is being forced down through the resin.



I'm pretty sure you do realize how they work, it's just your explaining makes it sound like the water line should be at the bottom of the canister.

 

[fishkeeprian]

When I first saw the DI Resin canister fill it was filling up the water around the side of the cartridge so I assume it's being pushed up through the Resin?

Thanks